Hydraulic power converter



Jan. 3, 1967 J. E.- SMITH 3,295,451

HYDRAULIC PO WER CONVERTER Filed Nov. 10, 1965 4 Sheets-Sheet 1INVENTOR.

BY JAMES .5. SM/ 777 Jan. 3, 1967 J. E. SMITH HYDRAULIC POWER CONVERTER4 Sheets-Sheet 2 Filed Nov. 10, 1965 FICA FIG,6 4.9

INVENTOR. JAMES E. SM/TH w/ww I Jan. 3, 1967 SMITH 3,295,451

HYDRAULIC POWER CONVERTER Filed Nov. 10. 1965 4 Sheets-Sheet 3 FIG] .INVENTOR. JA MES E. .S'M/FH i fiiw Jan. 3, 1967 J. E. SMITH 3,295,451

' HYDRAULIC POWER CONVERTER Filed Nov. 10,1965 4 Sheets-Sheet 4INVENTOR. JAMES E. SMITH United States Patent 25,25,451 HYDRAULIC POWERCONVERTER James E. Smith, 302 Plantation Drive,

Lake Jackson, Tex. 77566 Filed Nov. 10, 1965, Ser. No. 507,167 Claims.(Cl. 10349) The present application contains subject matter in commonwith my prior applications, Serial No. 175,767, new Patent No.3,162,133, and co-pending applications, Serial No. 436,972 and SerialNo. 420,028, filed December 21, 1964.

This invention relates to a hydraulic power converter for convertingfluid pressure from one fluid to use in moving another fluid ofdifferent viscosity, different pressure, or different consistency.Specifically, the present invention relates to a hydraulic powerconverter for transmitting fluid pressure from one fluid to anotherfluid that may be of a diflferent nature, such as a slurry containingsolids, without pulsation, and at a higher or lower pressure.

The present device is particularly useful for moving a solids ladenslurry in pipe lines or for industrial uses where it is necessary totransmit liquids or liquified material that would damage the powerproducing pumps it passed directly therethrough at very high pressures.The present device can be used for the transmission of fluids containingwood chips, abrasive laden fluids and the like under high pressurewithout pulsation and without damaging the equipment involved.

One of the principal objects of the present invention is to provide ahydraulic power converter device for moving large volumes of viscousfluids at high pressure without pulsation.

Another object is to provide a device with few moving parts andoperating on a substantially free piston plan whereby the hydraulicpower fluid and the fluid passing through, or being transmitted by theconverter, are kept separate so that abrasive slurries or fluids can bemoved at high pressure without damaging the intricate hydraulic powerpumps and supporting mechanism.

Still another object is to provide a device having timed inlet andoutlet valves to give positive opening and closing of the valves whenthe converter is used to move lumpy slurries through pipelines.

Still another object is to provide a hydraulic power converter having amain rotating distributor tube for dis- 'tributing the hydraulic powerfluid and the fluid or slurry passing through the convertersimultaneously in timed relation to a series of power transfer cylinderswith pistons reciprocating therein, positioned adjacent to the maindistributor member and connected therewith through a series of ports.

Still another object is to provide a free piston converter utilizing ahydraulic power pump in combination with a trapped reservoir of captivefluid for transmitting a fluid at high pressure continuously withoutpulsation.

These and other objects and advantages will become apparent hereinafter.

The present hydraulic power converter comprises a main distributormember and a series of power transfer cylinders (preferably three innumber) mounted adjacent to the main distributor member and connectedtherewith through a series of ports, each of the cylinders having freepistons separating a hydraulic power fluid and a captive fluid in atrapped reservoir behind or beneath the piston heads and interconnectedamong the cylinders at their lower ends.

The present converter uses fluid pressure to return the pistons withinthe cylinders to the top position, this return movement creating suctionin the extended portion of the cylinder in which the ram or plungerportion re- Patented Jan. 3, 1967 ciprocates. This action is caused bysaid fluid, which is a captive fluid trapped within the confines of thisportion of the converter. When hydraulic pressure is applied to thepiston head from its outside hydraulic power source to force said pistonto move downward in the cylinder, the fluid underneath this piston head,which is trapped around the annulus of the ram or plunger end, must bedisplaced into one or more of the other working cylinders. This featureprovides positive means for returning the pistons, without anymechanical help, and the upward movement is in phase with the openingsof discharge ports in the central valve tube. Therefore, the hydraulicfluid above the piston head is forced out and to pass through the fluidmotor which rotates said tube, and this action causes the valve tube (ortubes if more than one is used) to rotate, a measured amount to open orclose its ports in proper time with said fluid movement. This actionprovides the means for maintaining a constant overall suction andconstant overall discharge. What is meant by overall is the sum total ofall the working cylinders of the converter.

The invention also consists in the parts and in the arrangement andcombinations of parts hereinafter described and claimed.

In the accompanying drawing which forms part of this specification andwherein like numerals and symbols refer to like parts wherever theyoccur; FIG. 1 is a fragmentary vertical sectional view through theconverter showing the main distributor member and one of the pumpingcylinders;

FIG. 2 is an enlarged fragmentary view partly in section showing theconnection between the fluid pump and the distributor cylinder;

FIG. 3 is a view taken along line 33 of FIG. 2;

FIG. 4 is a diagrammatic sectional view showing the pumping cylinderlaid out on a plane;

FIG. 5 is a sectional view taken along line 55 of FIG. 4; showing thepumping cylinders arranged around the periphery of the distributorcylinder and showing the arrangement of the exhaust valves in thedistributor and the pumping cylinders;

FIG. 6 is a view similar to FIG. 5, but taken along lines 6-6 of FIG. 4and showing the arrangement of the inlet valves in the distributor andthe pressure fluid cylinders;

FIG. 7 is a fragmentary sectional view showing a modification of thepresent invention;

FIG. 8 is a diagrammatic arrangement showing the pumping system of thestructure of FIGS. l-6.

FIG. 9 is a diagrammatic view of the pumping system of the modificationshown in FIG. 7;

FIG. 10 is a fragmentary sectional view of another modification showingthe inlet and exhaust valves for the pumped fluids;

FIGS. l115 are fragmentary sectional views of the distributor andpumping cylinders taken along lines 11 11 to 15-15 respectively of FIG.1 showing the arrangement of the ports in the distributor cylinder andthe pumping cylinders.

Referring now to the drawings in detail, it will be seen that theembodiment of the invention which has been illustrated comprises ahydraulic power converter 10 comprising a main cylindrical housing 11which is closed by a bottom wall 12 and has a series of outwardlyextending arms 13 to which are affixed power transfer cylinder hous ings14 which also have closed bottom walls 15. A fluid motor 16 is mountedon the main housing 11 and has an output shaft 17 connected byappropriate gearing 18 (FIG. 2) to a main distributor member 19rotatably mounted in the cylindrical housing 11.

The main cylindrical housing 11 is provided with hydraulic actuating orpumping fluid entrance port 20 aligned 3 with a series of longitudinalslots 21 around the periphery of the distributor member 19 to admit thepressure fluid continuously and smoothly to a pumping fluid inletchamber 22 in the distributor member 19. The inlet ports are connectedto a fluid pump 23 by a conduit 24.

The main housing 11 also is provided with a pumping fluid exit port 25aligned with a series of longitudinal openings 26 in the distributor 19to exhaust pumping fluid from an exit chamber 27 to a conduit 28connected to the inlet side of the fluid motor 16. The exhaust side of.the fluid motor 16 is connected by a conduit 29 to a reservoir 30 andhence to the inlet side of the pump 23. Accordingly, as will beexplained in more detail hereinafter, the pump 23 moves the pumpingfluid through the converter 10 where it is utilized to move the pumpedfluid. When the pumping fluid leaves the converter 10 it is utilized inthe fluid motor 16 to rotate the main distributor member 19 and thenceis returned to the reservoir 30 before the pump 23 again cycles itthrough the converter 10.

The main housing 11 also is provided with an entrance port 31 for pumpedfluid connected to a conduit 32 and communicating with a pumping fluidinlet chamber 33 by a series of slots 34. The housing 11 also includesan exit port 35 for pumped fluid communicating with an exhaust chamber36 by a series of aligned openings 37 and with an exit conduit 38. Thepumped fluid inlet conduit 32 may be connected to a pipe line, to areservoir or some other means of pumped fluid. Similarly, the pumpedfluid discharge conduit 38 is connected to the appropriate destinationof the pumped fluid.

Arranged around the outer periphery of the distributor housing 11 are aseries of the pumping cylinder housings 14 preferably three in number.Each of the pumping cylinder housings 14 are provided with a main dam 39through which is slidable the stem 40 of a double headed free piston 41having a pumped fluid head 42 and a pumping fluid head 43.

Between the internal shoulder 44 of the pumping fluid head 43 and theopposed internal shoulder 45 of the dam 39 is defined an expansibletrapped fluid chamber 46. Each of the pumping cylinders 14 is providedwith a trapped fluid port 47 and is connected by means of a trappedfluid conduit 48 to the other pumping cylinders 14. This is shown inFIGS 4 and 11. Accordingly the trapped fluid is used to return thepiston heads 43 to their uppermost position when pumping fluid is notbeing delivered to the expansible pumping fluid chamber 49 between theexternal face 50 of the cylinder head 43 and the internal face of theclosure flange 13. The trapped fluid portions of the pumping cylinders14 are in constant and continuous communication among all of thecylinders .14 and this allows more than one of the pistons 41 to movesimultaneously in the same direction, thereby eliminating pulsation fromthe discharge line 38. Operation of the port arrangement to admitpumping fluid to more than one of the pumping cylinders 14simultaneously will be described hereinafter.

The main distributor member 19 is rotatable in the housing 14 and isdriven by the fluid motor 16 which operates from the pumping fluid, Thegearing 18 is so arranged that the main distributor 19 makes a complete360 rotation for a complete stroke of each of the pumping pistons 41. Inother words, as the distributor member 19 rotates, pumping fluid isadmitted to the pumping fluid chambers 49 alternately and pumped fluidis discharged from the expansible pumped fluid discharge chambers 51defined between the Working face 52 of the head 44 and the inner surfaceof bottom wall 15.

Starting from the top of the distributor member 19 the ports in thedistributor cylinder 19 and in the pumping cylinders 14 will bedescribed. The pumping cylinders 14 are identical and each operates inlike fashion but in timed sequence with the others as the distributormember 19 rotates so as to open and close the ports for the pumped fluidand the pumping fluid.

The distributor member 19 is provided first with the pumping fluid exitslots 26 aligned with the pumping fluid discharge port 25. These slots26 are equally spaced around the periphery of the distributor member 19and at. least one of them is in constant communication with thedischarge conduit 28 to assure a constant supply of pumping fluid to thefluid motor 16. The next port in the distributor member 19 is thepumping fluid exhaust.

port 53 which extends over approximately 6 of the circumference of thedistributor member 19 and is aligned with the pumping fluid dischargeports 54 in the pumping fluid chambers 49 of the pump cylinders 14. Thusas the distributor cylinder 19 rotates, the exhaust port 53 isalternately aligned with one or more of the cylinder ports 54 (FIG. 11)so as to admit pumping fluid to the exit chamber 27 from the pumpingfluid chamber 49 on the intake or upward stroke of the piston 41.

Moving downwardly, the next port in the distributor member 19 is thepumping fluid inlet port 55 which extends over approximately /3 of thecircumference of the distributor member 19 and is aligned With thepumping fluid inlet ports 56 in the pumping cylinders 14. When the ports55 and 56 are aligned (FIG. 12), pumping fluid is admitted to thechamber 49 and as the cylinder discharge port 54 is closed, the piston41 moves down- Wardly in the pumping cylinder 14 in its dischargestroke. This forces the trapped fluid from the chamber 46 to anothercylinder 14 (FIG. 11) where the discharge port 54 is open forcing thatpiston 41 upwardly on its intake 1 stroke, thus dischanging pumpingfluid from the chamber 49 and sucking pumped fluid into the chamber 51.

Continuing downwardly, the pumping fluid intake slots 21 and then thepumped fluid intake slots 34 are encountered,

The next port in the distributor member 19is the pumped fluid intakeport 57 which extends over approximately /3 of the circumference of thedistributor member 19 and is aligned with intake ports 58 communicatingwith the pumped fluid chamber 51 of the cylinders 14. When the ports 57and 58 are aligned, fluid is admitted to the chamber 51 on the upwardstroke of the piston 41. g

The exit ports 37 are spaced around the periphery of the distributormember 19 and aligned and in communication with the pumped fluiddischarge conduit 38 to insure a constant flow of pumped fluid withoutpulsa-. 1

tion from the converter 10.

The last port in the distributor member 19'is the pumped fluid dischargeport 59 which is aligned with dis-charge .ports 60 on the cylinders 14.The distributor port 59 extends over about /3 of the circumference andis adapted to be in communication with one or two of.

the cylinder discharge ports 60 at all times so as to in- The pumpingpiston face 52 is of less diameter than the piston face 50 so that thepressure of the pumped fluid is increased over that in the pumpingfluid. An oil seal arrangement 61 (FIG. 1) comprising an oil conduit 62,a reservoir 63, a pair of spaced oil rings 64 and i a discharge conduit65 provides a positive seal preventing the pumped fluid (which maycontain abrasives) from passing the front face of the piston 44. Anythat does pass is trapped in the space 66 between the body and 71 formedin the end of the rod 40. The piston head 52 engages a shoulder 72 inthe cylinder 14, and is thereby separated from the end 68 of the rod 40to pull oil into i the space 66 therebetween. When the piston 41 is dis-1 sure a constant flow of pumped fluid from the converter.

charging, the oil is forced into the reservoir 63 and lubricates thecylinder wall and forms a positive seal against moving of the pumpedfluid from the pumped fluid chamber 51 toward the trapped fluid chamber46.

Operation Very' briefly, the operation of the present invention allowstwo of the pumping cylinders 14 to be discharging pumped fluid orpumping fluid simultaneously so as to avoid any interruption in the flowof these fluids from the converter and thus prevents pulsation in theoutput from the converte-r 10. The operation will be described withreference to FIGS. 1, 46 and 11-15. As the distributor member 19rotates, the pumping fluid is discharged from the chamber 22 into thepumping fluid chamber 49 of a cylinder 14B (FIG. 4-6) through theinletport 56, the exhaust port 54 of this cylinder 14B being closed.This is the arrangement shown in FIGS. 1, 4-6 and 11-15. The arrangementshown in FIG. 1 corresponds generally to cylinder 14B of FIGS. 46, butFIGS. 4-6 are only to describe the operation schematically and are notaccurately related to FIGS. 1 and 11-15. This causes the piston 41 tomove downwardly forcing the trapped fluid out of the trapped fluidchamber 46 and into the corresponding chamber 46 of another cylinder 14Cwhe-re it moves that piston 41 upwardly. At the same time, the pumpedfluid in the pumped fluid chamber 51 is discharged through the ports 60and 59 into the chamber 36 and then through the ports 37 and into thedischarge conduit 38. As the distributor. member 19 continues to rotate,the port overlaps the inlet port 56 of the next adjacent pumpingcylinder 14A and starts to close on the inlet 56 of the pumping cylinder14A (FIG. 6). Thus pumpin-g fluid is being admitted to two of thepumping fluid chambers 49A and 49B simultaneously. The chamber piston41A starts to slow down as it reaches the bottom of its stroke and thepiston 4113, being at the top of its stroke, starts to move downwardlyin the discharge direction. The piston 41C, third cylinder, in themeantime is moving upwardly in its pumped fluid intake stroke. As thedistributor 19 continues to rotate, the pumping fluid inlet .port 56 inthe cylinder A is closed and the discharge port 54 is opened, so thatthe trapped fluid begins to be discharged from the cylinder 49A and isreturned to the trapped fluid chamber46C of the cylinder 14C and thepiston 41Cmoves upwardly discharging the pumping fluid through the nowopen port 54 and pulling the pumped fluid into the pumped fluid chamber51. This cycle is repeated to continue the pumping operation. Thisoperation gives an action to the pistons which is cushioned at thebeginning and end of the stroke so that there is no interruption of theflow and thus no pulsation. The pistons actually begin to move in thereturn direction before reaching a positive stop.

The ports in the distributor member and the cylinders are so arrangedand locate-d that as the fluid exit port closes, the fluid entrance portopens. Furthermore, the ports in the distributor member have a lengthsuch that they can overlap portions of corresponding ports in twoadjacent cylinders simultaneously, although at times the distributormember ports encounter only one cylinder port.

A modification of the invention is shown in FIG. 10 which utilizespoppet valves 80 in the pumped fluid conduit 81 rather than the rotationof the distributor member 19 of FIG. 1 to control flow of pumped fluidinto and out of the pumped fluid chambers 51a of the pumping cylinders14a. In this arrangement, the operation of the pumping fluid portion ofthe rotating distributor member 19a is the same as that herein beforedescribed. The main casings 11a and the distributor member 19a terminateat what would be the top of the chamber 33 in the structure of FIG. 1.The pumped fluid discharge lines 81 are all connected to a commondischarge conduit (not shown) designed to provide a continuous outputfrom the converter 10a. The poppet valves 89 operate in the usualfashion so that when the piston head 42a is moving upwardly, the intakevalve a is open, and the discharge valve 80b is closed, and when thepiston 42a is moving downwardly on its discharge stroke, the inlet valve8ia is closed and the discharge valve 80b is open.

Another modification of the present invention is shown in FIGS. 7 and 9which is useful if only a portion of the pumping fluid is to be used indriving the fluid motor 16a. In this arrangement, the pumping cylinders14 are provided with a fixed center conduit 82 slidably mounted in awell 83 in the pumping fluid piston head 43a. This arrangement issubstituted for the corresponding piston head 43 of FIG. 1, and operatessimilarly except that the valve 84 is opened on the intake stroke of thepiston 43a to let pumping fluid from the conduit 85 into the tube 82. Onthe outward stroke of the piston head 43a, the valve 84 closes and thefluid in the tube 82 is moved through the manifold 86 to the fluid motor16a. The remainder of the pumping fluid is discharged from the chamber49a through the port 54a to a conduit 87 by which it is returned to thereservoir 88. This arrangement is shown schematically in FIG. 9. In thisdiagram, a pump is omitted. The pumping fluid from the reservoir 88 ismoved by the pump through the conduit 89 to the distributor 1% where itis passed by the port 56a to the chamber 4% and also by the conduit 85(whose connection .to the conduit 89 is not shown, but is by a standardmanifold arrangement) to the well 83.

Another modification shown in FIG. 7 includes the standard fillmechanism for the captive fluid chamber 45a which includes trip member90 for allowing more captive fluid into the system from a reservoir whenthe head 43a engages the trip 90, and the trip 91 for dischargingcaptive fluid from the chamber 46a when the trip 91 is engaged by thehead 43a. This arrangement can be used with any of the structures shown.

Another advantage of the present invention lies in its use as a boosterstation in a pipe line. As is known, the fluid in a pipe line'losespressure along its length. With the present invention a fluid containingabrasive solids (which would damage a conventional pump) can be boostedin pressure without losing the pressure remaining in the fluid. Forexample, the fluid may enter the pumped fluid cylinders at 2000 p.s.i.and to boost this to 5000 p.s.i., the converter adds only 3000 p.s.i. tothe fluid. The pressure remaining in the fluid entering the converter ispicked up by the trapped fluid through the piston and transferred to theoperating cylinders.

Thus it is seen that the present invention provides a converterachieving all the objects and advantages sought therefor.

This invention is intended to cover all changes and modifications of theexample of the invention herein chosen for purposes of the disclosure,which do not constitute departures from the spirit and scope of theinvention.

What is claimed is:

1. A hydraulic power converter comprising:

(a) a source of pressurized hydraulic actuating fluid,

(b) main distributor inlet and exhaust ports communicating with thepressurized actuating fluid source,

(c) at least three power transfer cylinders, each of the cylindershaving:

(1) a dam positioned therein, (2) a piston mounted for reciprocalmovement in the cylinder, said piston including:

(a) a stem slidable through the dam, (b) heads on opposite ends of thepistons, (c) the piston heads, dam and cylinder defining expansiblechambers between the heads and the ends of the cylinder and a trappedfluid chamber between the dam and the inner face of the head exposed tothe actuating fluid,

(3) actuating fluid inlet and exhaust ports aligned with the distributoractuating fluid inlet and exhaust ports,

(d) means connecting at all times the trapped fluid expansi-ble chambersin the cylinders,

(e) means for alternately and in turn moving the distributor actuatingfluid inlet and exhaust ports into and out of communication with theinlet and exhaust ports of each of the cylinders, and

(f) pumped fluid inlet and exhaust means communicating with theexpansible pumped fluid chambers in the power transfer cylinders andtimed with the operation of the pistons to deliver a continuous,uninterrupted non-pulsating output of pumped fluid from the converter. I

2. The structure of claim 1 wherein the inlet and exhaust ports arealternately gradually opened and closed with more than one of thepistons movable in the same direction simultaneously, and with thepistons accelerating and decelerating during their travel in thecylinders.

3. The structure of claim 2 including a main distributor member in whichthe distributor ports are located, said member being adjacent to thepower transfer cylinders, and a fluid motor operated by the actuatingfluid and having an output shaft connected to the main member forrotating the same.

4. The structure of claim 3 wherein the pumped fluid inlet and exhaustmeans are ports in the main distributor member and are aligned withcorresponding ports in the power transfer cylinders. V

5. The structure of claim 1 including a separable head on the pumpedfluid end of the piston, an oil seal means for effecting a positive sealbetween the pumped fluid and the trapped fluid to prevent contaminationof the trapped fluid by the pumped fluid.

6. The structure of claim 1 including means for moving only a portion ofthe actuating fluid through the fluid motor.

7. The structure of claim 1 including means for maintaining the volumeof trapped fluid in the system between predetermined levels.

8. The structure of claim 3 wherein the inlet and ex- (b) a fluid motoroperated by the actuating fluid and operatively connected to thedistributor member for rotating said distributor member, and

(c) the inlet and exhaust ports in the distributor member being of alength to intersect more than one corresponding port in the powertransfer cylinders and wherein the ports are so located that an inlet,

port into a cylinder is closed as the exhaust port in said cylinder isopened.

10. The structure of claim 9 including pumped fluid inlet and exhaustports in the main distributor member, and corresponding aligned ports inthe cylinders, the distributor ports being of a length to intersect morethan one corresponding port in the cylinders, and Where the cylindersare so located that an exhaust port is closed as the inlet port in saidcylinder is opened.

References Cited by the Examiner UNITED STATES PATENTS 2,112,466 3 /1938Maloon 6o .5,2 2,486,079 10/1949 Tucker 103. 49

FOREIGN PATENTS 518,840 2/1931 Germany.

EDGAR W. GEOGHEGAN, Primary Examiner.

1. A HYDRAULIC POWER CONVERTER COMPRISING: (A) A SOURCE OF PRESSURIZEDHYDRAULIC ACTUATING FLUID, (B) MAIN DISTRIBUTOR INLET AND EXHAUST PORTSCOMMUNICATING WITH THE PRESSURIZED ACTUATING FLUID SOURCE, (C) AT LEASTTHREE POWER TRANSFER CYLINDERS, EACH OF THE CYLINDERS HAVING: (1) A DAMPOSITIONED THEREIN, (2) A PISTON MOUNTED FOR RECIPROCAL MOVEMENT IN THECYLINDER, SAID PISTON INCLUDING: (A) A STEM SLIDABLE THROUGH THE DAM,(B) HEADS ON OPPOSITE ENDS OF THE PISTONS, (C) THE PISTON HEADS, DAM ANDCYLINDER DEFINING EXPANSIBLE CHAMBERS BETWEEN THE HEADS AND THE ENDS OFTHE CYLINDER AND A TRAPPED FLUID CHAMBER BETWEEN THE DAM AND THE INNERFACE OF THE HEAD EXPOSED TO THE ACTUATING FLUID, (3) ACTUATING FLUIDINLET AND EXHAUST PORTS ALIGNED WITH THE DISTRIBUTOR ACTUATING FLUIDINLET AND EXHAUST PORTS, (D) MEANS CONNECTING AT ALL TIMES THE TRAPPEDFLUID EXPANSIBLE CHAMBERS IN THE CYLINDERS, (E) MEANS FOR ALTERNATELYAND IN TURN MOVING THE DISTRIBUTOR ACTUATING FLUID INLET AND EXHAUSTPORTS INTO AND OUT OF COMMUNICATION WITH THE INLET AND EXHAUST PORTS OFEACH OF THE CYLINDERS, AND (F) PUMPED FLUID INLET AND EXHAUST MEANSCOMMUNICATING WITH THE EXPANSIBLE PUMPED FLUID CHAMBERS IN THE POWERTRANSFER CYLINDERS AND TIMED WITH THE OPERATION OF THE PISTONS TODELIVER A CONTINUOUS, UNINTERRUPTED NON-PULSATING OUTPUT OF PUMPED FLUIDFROM THE CONVERTER.